Insulation of homes with cellulose wadding represents a small part of the insulation market, but has seen very strong growth in recent years. Ammonium salts may be added to the cellulose wadding in order to improve its resistance to fire. However, under certain conditions (especially with high relative humidity), these salts may release ammonia gas inside the dwelling. This gas is irritating to mucous membranes and the respiratory tract.
French toxicovigilance data collected in 2012 and the first half of 2013 show that some forty patients presented with symptoms characteristic of the effects of this substance (irritation of the upper airways, cough, or even asthma decompensation in one asthmatic child) in dwellings that had recently been insulated with cellulose wadding. In this context, in June 2013, the placing on the market, import, sale or distribution and manufacture of cellulose wadding insulation containing ammonium salts were prohibited in France.
Following European Commission Implementing Decision of 14 October 2013 authorising the provisional measure taken by France, and in accordance with the emergency procedure referred to in the REACh Regulation, ANSES was commissioned to prepare a restriction dossier within three months of the date of the Commission Decision.
In its restriction proposal, ANSES considers that ammonium salts can only be used if the ammonia gas emissions are below a threshold of 3 parts per million (ppm) under well-defined test conditions. The proposed test is based on technical specification CEN/TS 16516 with the adaptation of certain parameters. This method can be used to determine the specific emission rate of volatile compounds emitted from a construction product in indoor air.
The content of the restriction dossier does not include an assessment of the risks posed by alternative formulations (based on boron) currently used as additives in cellulose wadding and containing boron salts). Indeed, the Agency believes that these compounds cannot be regarded as an alternative given their toxicity to reproduction. To date, no safe, technically and economically viable alternative has been identified, although research is underway in France to develop new formulations. With this in mind, ammonium salts are an option, provided that the formulations do not cause the release of ammonia gas above the limit established by the restriction proposal.
All the information found in the restriction dossier proposed by ANSES is summarised in the Opinion it is publishing today.
Public consultation by ECHA until 18 December 2014
On 18 June 2014, this proposal was submitted for public consultation on the ECHA website, for a period of six months. Following this consultation stage, the ECHA Committees for Risk Assessment and Socio-economic Analysis will issue a final opinion, on the basis of all the data, which will be sent to the European Commission for a decision on whether or not to include ammonium saltsin Annex XVII of the REACh Regulation.
This proposal should significantly reduce ammonia gas emissions, thereby helping to ensure effective management of the identified health risks for consumers in all the Member States of the European Union.
 Ministerial Order of 21 June 2013 on the prohibition of the placing on the market, import, sale and distribution, and manufacture of cellulose wadding insulation containing ammonium salts.
 XP CEN/TS 16516 December 2013. Construction products – Assessment of release of dangerous substances – Determination of emissions into indoor air.